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David Julian Mcclements - One of the best experts on this subject based on the ideXlab platform.
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Encapsulation of lipophilic polyphenols in plant-based nanoemulsions: impact of Carrier Oil on lipid digestion and curcumin, resveratrol and quercetin bioaccessibility
Food & Function, 2021Co-Authors: Hualu Zhou, Bingjing Zheng, David Julian McclementsAbstract:The gastrointestinal fate of emulsified lipophilic polyphenols depends on the nature of the Carrier Oil used to deliver them.
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Fabrication of plant-based vitamin D3-fortified nanoemulsions: influence of Carrier Oil type on vitamin bioaccessibility.
Food & function, 2019Co-Authors: Anna Larissa Schoener, Ruojie Zhang, Jochen Weiss, David Julian McclementsAbstract:The influence of Carrier Oil type (corn, fish, or flaxseed Oil) on the production, stability, and simulated gastrointestinal behavior of vitamin-fortified nanoemulsions was studied. The nanoemulsions were formulated using pea protein as an emulsifier since there is increasing interest in substituting artificial and animal-based food ingredients with natural plant-based alternatives. Lipid digestion and vitamin D3 bioaccessibility were measured when the nanoemulsions were subjected to a three-stage in vitro gastrointestinal tract: oral, gastric, and small intestinal. The majority of all three lipids were digested within the first few minutes in the simulated small intestine, with the corn Oil nanoemulsions being digested faster than the fish or flaxseed Oils. Moreover, a greater fraction of triglycerides were digested by the end of the small intestine for the corn Oil than for the fish and flaxseed Oils. For the different Carrier Oils, vitamin bioaccessibility was ranked: corn Oil > flaxseed Oil ≈ fish Oil. These results suggest that monounsaturated-rich Oils (such as corn Oil) are better for encapsulating and delivering vitamin D3 than polyunsaturated-rich ones (such as flaxseed or fish Oil). The insights gained here may aid in the formulation of more efficacious vitamin-fortified foods and beverages from plant-derived ingredients.
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Bioaccessibility and cellular uptake of β-carotene in emulsion-based delivery systems using scallop (Patinopecten yessoensis) gonad protein isolates: effects of Carrier Oil.
Food & function, 2019Co-Authors: Jia-run Han, David Julian Mcclements, Ruojie Zhang, Wen-hui Shang, Jia-nan Yan, Beiwei Zhu, Hang XiaoAbstract:Emulsion-based delivery systems were structured by using scallop gonad protein isolates (SGPIs) as novel food-grade emulsifiers. The effects of Carrier Oil, including the long chain triglycerides (LCT) and medium chain triglycerides (MCT), on the bioaccessibility and cellular uptake of β-carotene (BC) were investigated. Both LCT and MCT delivery systems remained stable at pH 7–8 but aggregated at lower pH values (3–6) according to the results of light scattering and microscopy measurements. LCT droplets fabricated within SGPIs were digested and released more slowly than MCT droplets during the simulated gastrointestinal tract digestion. The LCT emulsion showed higher BC bioaccessibility (65.5%) than the MCT emulsion (23.1%) as a result of the greater solubilization of BC in mixed micelles fabricated from long-chain fatty acids. Moreover, the LCT emulsion produced higher cellular uptake of BC as compared with the MCT emulsion in intestinal epithelial cells. These results demonstrated that SGPIs could be used as novel food-grade emulsifiers to protect lipophilic bioactive compounds in emulsion-based delivery systems, in which LCT is more suitable to encapsulate and deliver BC than MCT.
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Vitamin E Encapsulation in Plant-Based Nanoemulsions Fabricated Using Dual-Channel Microfluidization: Formation, Stability, and Bioaccessibility
Journal of agricultural and food chemistry, 2018Co-Authors: Ruojie Zhang, Yanhua Zhang, Haiyan Tan, David Julian McclementsAbstract:In this study, vitamin E was encapsulated in Oil-in-water nanoemulsions fabricated using a dual-channel microfluidizer. A long chain triacylglycerol (corn Oil) was used as a Carrier Oil and a biosurfactant (quillaja saponin) was used as a natural emulsifier. The impact of vitamin-to-Carrier Oil ratio on the formation, storage stability, and bioaccessibility of the nanoemulsions was determined. The lipid droplet size formed during homogenization increased with increasing vitamin content, which was attributed to a large increase in lipid phase viscosity. The storage stability of the nanoemulsions decreased as the vitamin content increased because the larger lipid droplets creamed faster. The rate and extent of lipid hydrolysis in the small intestine decreased as the vitamin content increased, probably because the vitamin molecules inhibited the ability of lipase to reach the triacylglycerols inside the lipid droplets. Vitamin bioaccessibility decreased as the vitamin level in the lipid phase increased, which was attributed to the reduced level of mixed micelles available to solubilize the tocopherols. The optimized nanoemulsion-based delivery system led to a relatively high vitamin bioaccessibility (53.9%). This research provides valuable information for optimizing delivery systems to increase the bioaccessibility of Oil-soluble vitamins.
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vitamin e encapsulation in plant based nanoemulsions fabricated using dual channel microfluidization formation stability and bioaccessibility
Journal of Agricultural and Food Chemistry, 2018Co-Authors: Shanshan Lv, Ruojie Zhang, Jiyou Gu, Yanhua Zhang, David Julian McclementsAbstract:In this study, vitamin E was encapsulated in Oil-in-water nanoemulsions fabricated using a dual-channel microfluidizer. A long chain triacylglycerol (corn Oil) was used as a Carrier Oil and a biosurfactant (quillaja saponin) was used as a natural emulsifier. The impact of vitamin-to-Carrier Oil ratio on the formation, storage stability, and bioaccessibility of the nanoemulsions was determined. The lipid droplet size formed during homogenization increased with increasing vitamin content, which was attributed to a large increase in lipid phase viscosity. The storage stability of the nanoemulsions decreased as the vitamin content increased because the larger lipid droplets creamed faster. The rate and extent of lipid hydrolysis in the small intestine decreased as the vitamin content increased, probably because the vitamin molecules inhibited the ability of lipase to reach the triacylglycerols inside the lipid droplets. Vitamin bioaccessibility decreased as the vitamin level in the lipid phase increased, whic...
Hang Xiao - One of the best experts on this subject based on the ideXlab platform.
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Bioaccessibility and cellular uptake of β-carotene in emulsion-based delivery systems using scallop (Patinopecten yessoensis) gonad protein isolates: effects of Carrier Oil.
Food & function, 2019Co-Authors: Jia-run Han, David Julian Mcclements, Ruojie Zhang, Wen-hui Shang, Jia-nan Yan, Beiwei Zhu, Hang XiaoAbstract:Emulsion-based delivery systems were structured by using scallop gonad protein isolates (SGPIs) as novel food-grade emulsifiers. The effects of Carrier Oil, including the long chain triglycerides (LCT) and medium chain triglycerides (MCT), on the bioaccessibility and cellular uptake of β-carotene (BC) were investigated. Both LCT and MCT delivery systems remained stable at pH 7–8 but aggregated at lower pH values (3–6) according to the results of light scattering and microscopy measurements. LCT droplets fabricated within SGPIs were digested and released more slowly than MCT droplets during the simulated gastrointestinal tract digestion. The LCT emulsion showed higher BC bioaccessibility (65.5%) than the MCT emulsion (23.1%) as a result of the greater solubilization of BC in mixed micelles fabricated from long-chain fatty acids. Moreover, the LCT emulsion produced higher cellular uptake of BC as compared with the MCT emulsion in intestinal epithelial cells. These results demonstrated that SGPIs could be used as novel food-grade emulsifiers to protect lipophilic bioactive compounds in emulsion-based delivery systems, in which LCT is more suitable to encapsulate and deliver BC than MCT.
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nanoemulsion based delivery systems for nutraceuticals influence of Carrier Oil type on bioavailability of pterostilbene
The FASEB Journal, 2015Co-Authors: Yue Sun, David Julian Mcclements, Peiju Qiu, Ziyuan Xia, Jinkai Zheng, Lijuan Zhang, Hang XiaoAbstract:Food-grade delivery systems are essential to improve bioavailability of nutraceuticals. Pterostilbene is a dietary flavonoid with various beneficial effects, but a low bioavailability. We determined the influence of nanoemulsion-based delivery systems with different Carrier Oils (flaxseed Oil vs. olive Oil) on the bioaccessibility and bioavailability of pterostilbene. The nanoemulsions were subjected to a simulated gastrointestinal tract (GIT) which include mouth, stomach and small intestine, then the resulting micelles were subject to absorption and metabolism study in the Caco-2 cell. The amounts of non-conjugated and conjugated pterostilbene in the cells, apical and basolateral compartments were detected by HPLC. The bioaccessibility of pterostilbene in both nanoemulsions were significantly higher than the control (non-encapsulated) group. The nanoemulsion containing olive Oil had a higher extent of free fatty acid production in the small intestine than flaxseed Oil one, it also increased trans-enteroc...
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Nanoemulsion-based delivery systems for nutraceuticals: Influence of Carrier Oil type on bioavailability of pterostilbene
Journal of Functional Foods, 2015Co-Authors: Yue Sun, David Julian Mcclements, Peiju Qiu, Ziyuan Xia, Jinkai Zheng, Lijuan Zhang, Hang XiaoAbstract:Nanoemulsion-based delivery systems can be utilized in functional foods and beverages to improve the bioavailability of nutraceuticals. We determined the influence of Carrier Oil type on the bioavailability of pterostilbene encapsulated in nanoemulsions containing either flaxseed or olive Oil as the Carrier Oil. The nanoemulsions were then subjected to a simulated gastrointestinal tract (mouth, stomach, small intestine), and the resulting micelle phases were used to establish pterostilbene bioavailability using a Caco-2 cell model. Both nanoemulsions significantly enhanced the bioaccessibility of pterostilbene within the micelle phase. However, olive Oil nanoemulsions increased trans-enterocyte transport of pterostilbene more effectively than flaxseed Oil ones. Moreover, the patterns of metabolism of pterostilbene during its trans-enterocyte transport were dramatically different when pterostilbene was delivered using nanoemulsions with different Carrier Oil types.
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nutraceutical nanoemulsions influence of Carrier Oil composition digestible versus indigestible Oil on β carotene bioavailability
Journal of the Science of Food and Agriculture, 2013Co-Authors: Eric A Decker, Hang Xiao, David Julian McclementsAbstract:BACKGROUND Carotenoids, such as β-carotene, are widely used in foods and beverages as natural colorants and nutraceuticals. We investigated the influence of Carrier Oil composition (ratio of digestible to indigestible Oil) on the physical stability, microstructure and bioaccessibility of β-carotene nanoemulsions using a simulated gastrointestinal tract model. RESULTS β-Carotene nanoemulsions (d < 150 nm) were formed by high-pressure homogenization using sucrose monoester and lysolecithin as emulsifiers, and mixtures of corn Oil (digestible) and lemon Oil (indigestible) as the lipid phase. All of the nanoemulsions underwent extensive droplet aggregation under mouth, stomach and small intestine conditions. The extent of free fatty acid production in the small intestine increased as the amount of digestible Oil in the droplets increased. The bioaccessibility of β-carotene also increased with increasing digestible Oil content, ranging from ∼5% for the pure lemon Oil system to ∼76% for the pure corn Oil system. This effect was attributed to the ability of mixed micelles formed from triglyceride digestion products (free fatty acids and monoglycerides) to solubilize β-carotene. CONCLUSIONS This study provides important information for developing effective delivery systems for lipophilic bioactive components in food and beverage applications. © 2013 Society of Chemical Industry
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Nutraceutical nanoemulsions: influence of Carrier Oil composition (digestible versus indigestible Oil) on β-carotene bioavailability.
Journal of the science of food and agriculture, 2013Co-Authors: Jiajia Rao, Eric A Decker, Hang Xiao, David Julian McclementsAbstract:BACKGROUND Carotenoids, such as β-carotene, are widely used in foods and beverages as natural colorants and nutraceuticals. We investigated the influence of Carrier Oil composition (ratio of digestible to indigestible Oil) on the physical stability, microstructure and bioaccessibility of β-carotene nanoemulsions using a simulated gastrointestinal tract model. RESULTS β-Carotene nanoemulsions (d < 150 nm) were formed by high-pressure homogenization using sucrose monoester and lysolecithin as emulsifiers, and mixtures of corn Oil (digestible) and lemon Oil (indigestible) as the lipid phase. All of the nanoemulsions underwent extensive droplet aggregation under mouth, stomach and small intestine conditions. The extent of free fatty acid production in the small intestine increased as the amount of digestible Oil in the droplets increased. The bioaccessibility of β-carotene also increased with increasing digestible Oil content, ranging from ∼5% for the pure lemon Oil system to ∼76% for the pure corn Oil system. This effect was attributed to the ability of mixed micelles formed from triglyceride digestion products (free fatty acids and monoglycerides) to solubilize β-carotene. CONCLUSIONS This study provides important information for developing effective delivery systems for lipophilic bioactive components in food and beverage applications. © 2013 Society of Chemical Industry
Eric A Decker - One of the best experts on this subject based on the ideXlab platform.
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improvements in the formation and stability of fish Oil in water nanoemulsions using Carrier Oils mct thyme Oil lemon Oil
Journal of Food Engineering, 2017Co-Authors: Rebecca M Walker, Eric A Decker, Cansu Ekin Gumus, David Julian McclementsAbstract:Abstract Nanoemulsion-based delivery systems are particularly effective tools for incorporating omega-3 polyunsaturated lipids into many foods and beverages. In this study, the impact of Carrier Oil type and concentration on the formation and stability of fish Oil-in-water nanoemulsions was determined. Three Carrier Oils with different physicochemical and sensory properties were evaluated: medium chain triglycerides (MCT); lemon Oil; and thyme Oil. Nanoemulsions (d thyme Oil. This effect was attributed to the presence of high levels of natural antioxidants (phenolics) within the lemon and thyme Oils. These results show that selection of an appropriate Carrier Oil type and concentration can lead to the formation of fish Oil nanoemulsions with good physical and chemical stability.
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influence of whey protein beet pectin conjugate on the properties and digestibility of β carotene emulsion during in vitro digestion
Food Chemistry, 2014Co-Authors: Fang Yuan, David Julian Mcclements, Yanxiang Gao, Atikorn Panya, Eric A DeckerAbstract:The impact of a whey protein isolate (WPI)–beet pectin (BP) conjugate (formed by dry-heating) on the physical properties and digestibilities of β-carotene and Carrier Oil in Oil-in-water emulsions was studied when they passed through a model gastrointestinal system. β-Carotene emulsions were stabilized by WPI, unconjugated and conjugated WPI–BP, separately. The emulsions were then passed through an in vitro digestion model and the mean droplet size, droplet distribution, zeta-potential, free fatty acids and β-carotene released were measured. The stability to droplet flocculation and coalescence during digestion was increased for the WPI–BP conjugate stabilized emulsion. Addition of BP onto the WPI stabilized emulsions could inhibit the releases of Carrier Oil (MCT) and β-carotene. The releases of free fatty acids and β-carotene did not differ greatly between the unconjugated and conjugated WPI–BP stabilized emulsions. These results have important implications for protein–polysaccharide stabilized emulsions and conjugates used for the protection and delivery of bioactive compounds.
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nutraceutical nanoemulsions influence of Carrier Oil composition digestible versus indigestible Oil on β carotene bioavailability
Journal of the Science of Food and Agriculture, 2013Co-Authors: Eric A Decker, Hang Xiao, David Julian McclementsAbstract:BACKGROUND Carotenoids, such as β-carotene, are widely used in foods and beverages as natural colorants and nutraceuticals. We investigated the influence of Carrier Oil composition (ratio of digestible to indigestible Oil) on the physical stability, microstructure and bioaccessibility of β-carotene nanoemulsions using a simulated gastrointestinal tract model. RESULTS β-Carotene nanoemulsions (d < 150 nm) were formed by high-pressure homogenization using sucrose monoester and lysolecithin as emulsifiers, and mixtures of corn Oil (digestible) and lemon Oil (indigestible) as the lipid phase. All of the nanoemulsions underwent extensive droplet aggregation under mouth, stomach and small intestine conditions. The extent of free fatty acid production in the small intestine increased as the amount of digestible Oil in the droplets increased. The bioaccessibility of β-carotene also increased with increasing digestible Oil content, ranging from ∼5% for the pure lemon Oil system to ∼76% for the pure corn Oil system. This effect was attributed to the ability of mixed micelles formed from triglyceride digestion products (free fatty acids and monoglycerides) to solubilize β-carotene. CONCLUSIONS This study provides important information for developing effective delivery systems for lipophilic bioactive components in food and beverage applications. © 2013 Society of Chemical Industry
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Nutraceutical nanoemulsions: influence of Carrier Oil composition (digestible versus indigestible Oil) on β-carotene bioavailability.
Journal of the science of food and agriculture, 2013Co-Authors: Jiajia Rao, Eric A Decker, Hang Xiao, David Julian McclementsAbstract:BACKGROUND Carotenoids, such as β-carotene, are widely used in foods and beverages as natural colorants and nutraceuticals. We investigated the influence of Carrier Oil composition (ratio of digestible to indigestible Oil) on the physical stability, microstructure and bioaccessibility of β-carotene nanoemulsions using a simulated gastrointestinal tract model. RESULTS β-Carotene nanoemulsions (d < 150 nm) were formed by high-pressure homogenization using sucrose monoester and lysolecithin as emulsifiers, and mixtures of corn Oil (digestible) and lemon Oil (indigestible) as the lipid phase. All of the nanoemulsions underwent extensive droplet aggregation under mouth, stomach and small intestine conditions. The extent of free fatty acid production in the small intestine increased as the amount of digestible Oil in the droplets increased. The bioaccessibility of β-carotene also increased with increasing digestible Oil content, ranging from ∼5% for the pure lemon Oil system to ∼76% for the pure corn Oil system. This effect was attributed to the ability of mixed micelles formed from triglyceride digestion products (free fatty acids and monoglycerides) to solubilize β-carotene. CONCLUSIONS This study provides important information for developing effective delivery systems for lipophilic bioactive components in food and beverage applications. © 2013 Society of Chemical Industry
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impact of lipid nanoparticle physical state on particle aggregation and β carotene degradation potential limitations of solid lipid nanoparticles
Food Research International, 2013Co-Authors: Cheng Qian, Hang Xiao, Eric A Decker, David Julian McclementsAbstract:Abstract The impact of Carrier Oil composition and physical state on the physical and chemical stability of lipid nanoparticles containing encapsulated β-carotene was investigated. Lipid nanoparticles ( d C ) was ≈ 20 for SLN and ≈ 12 for LLN. These effects were attributed to the ability of the fat crystals within the lipid nanoparticles to promote partial coalescence and expulsion of carotenoids to the particle exterior. This study shows that solid lipid nanoparticles may not be better than liquid lipid nanoparticles for encapsulation of bioactive food ingredients.
Cheng Qian - One of the best experts on this subject based on the ideXlab platform.
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modulating β carotene bioaccessibility by controlling Oil composition and concentration in edible nanoemulsions
Food Chemistry, 2013Co-Authors: Laura Salviatrujillo, Cheng Qian, Olga Martinbelloso, David Julian McclementsAbstract:Diets rich in carotenoids have been correlated with a reduced risk of developing certain types of chronic diseases, but these bioactive components have low intestinal absorption due to their hydrophobic nature. The aim of this work was to study the effect of Carrier Oil composition (medium-chain triglyceride (MCT) to long-chain triglyceride (LCT) ratio) and total Carrier Oil concentration (1% or 4% w/w) on the physical stability, lipid digestibility and bioaccessibility of β-carotene-loaded nanoemulsions, using a simulated digestion process. Lipolysis led to an appreciable increase in the size and negative charge on the particles in the system. The total fraction of triacylglycerols converted to free fatty acids decreased as the percentage of LCT within the lipid phase increased, particularly for the nanoemulsions with higher fat contents. There was an increase in β-carotene bioaccessibility as the LCT within the lipid phase increased for low fat nanoemulsions, which was attributed to the increased solubilisation capacity of mixed micelles formed by LCT. β-carotene bioaccessibility showed a complex relationship on LCT content for high fat nanoemulsions, due to the opposing effects of lipid digestion and micelle solubilisation. These results may facilitate the optimisation of delivery systems for lipophilic bioactive compounds for food or pharmaceutical applications.
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impact of lipid nanoparticle physical state on particle aggregation and β carotene degradation potential limitations of solid lipid nanoparticles
Food Research International, 2013Co-Authors: Cheng Qian, Hang Xiao, Eric A Decker, David Julian McclementsAbstract:Abstract The impact of Carrier Oil composition and physical state on the physical and chemical stability of lipid nanoparticles containing encapsulated β-carotene was investigated. Lipid nanoparticles ( d C ) was ≈ 20 for SLN and ≈ 12 for LLN. These effects were attributed to the ability of the fat crystals within the lipid nanoparticles to promote partial coalescence and expulsion of carotenoids to the particle exterior. This study shows that solid lipid nanoparticles may not be better than liquid lipid nanoparticles for encapsulation of bioactive food ingredients.
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nanoemulsion delivery systems influence of Carrier Oil on β carotene bioaccessibility
Food Chemistry, 2012Co-Authors: Cheng Qian, Hang Xiao, Eric A Decker, David Julian McclementsAbstract:Abstract Consumption of carotenoids may reduce the incidences of certain chronic diseases, but their use in foods is currently limited because of their poor water-solubility, low bioavailability and chemical instability. We examined the impact of Carrier Oil type on the bioaccessibility of β-carotene encapsulated within nanoemulsion-based delivery systems. Oil-in-water nanoemulsions ( d in vitro model to simulate the oral, gastric and small intestinal phases of the gastrointestinal tract. The rate and extent of free fatty acid production in the intestine decreased in the order LCT ≈ MCT ≫ orange Oil; whereas β-carotene bioaccessibility decreased in the order LCT ≫ MCT > orange Oil. The bioaccessibility of β-carotene was negligible (≈0%) in orange Oil nanoemulsions because no mixed micelles were formed to solubilise β-carotene, and was relatively low (≈2%) in MCT nanoemulsions because the mixed micelles formed were too small to solubilise β-carotene. In contrast, β-carotene bioaccessibility was relatively high (≈66%) in LCT nanoemulsions. Our results have important implications for the design of effective delivery systems for encapsulation of carotenoids and other lipophilic bioactive components.
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Solid Lipid Nanoparticles: Effect of Carrier Oil and Emulsifier Type on Phase Behavior and Physical Stability
Journal of the American Oil Chemists' Society, 2012Co-Authors: Cheng Qian, Hang Xiao, Eric Andrew Decker, David Julian McclementsAbstract:The impact of surfactant type and Carrier Oil type on the phase behavior and physical stability of emulsified tripalmitin was investigated. Solid lipid nanoparticles (SLNs) were prepared by homogenizing lipid and aqueous phases at a temperature (≈80 °C) above the melting point of tripalmitin, and then cooling the resulting Oil-in-water emulsion to induce lipid droplet crystallization. When stored at 37 °C, tripalmitin particles had good long-term stability ( d
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Solid Lipid Nanoparticles: Effect of Carrier Oil and Emulsifier Type on Phase Behavior and Physical Stability
Journal of the American Oil Chemists' Society, 2011Co-Authors: Cheng Qian, Hang Xiao, Eric A Decker, David Julian McclementsAbstract:The impact of surfactant type and Carrier Oil type on the phase behavior and physical stability of emulsified tripalmitin was investigated. Solid lipid nanoparticles (SLNs) were prepared by homogenizing lipid and aqueous phases at a temperature (≈80 °C) above the melting point of tripalmitin, and then cooling the resulting Oil-in-water emulsion to induce lipid droplet crystallization. When stored at 37 °C, tripalmitin particles had good long-term stability (d < 150 nm) when coated with Tween 20, but were prone to aggregation and gelation when coated with modified starch (MS). Conversely, when stored at ≤20 °C tripalmitin particles coated by MS were more stable to aggregation/gelation than those coated by Tween 20. Blending tripalmitin with low melting point lipids (either medium chain triglycerides or orange Oil) prior to homogenization led to a considerable alteration in the SLN phase behavior and stability. DSC measurements indicated that the presence of the Carrier Oils reduced the crystallization temperature, melting temperature, and melting enthalpy of tripalmitin. In addition, the Carrier Oils improved the stability of SLNs to particle aggregation and gelation, although some particle coalescence still occurred. These results have important implications for formulating colloidal delivery systems for utilization within the food and other industries.
Antigoni Alexandrou - One of the best experts on this subject based on the ideXlab platform.
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Red Blood Cell Sickling During Oxygen Cycles in a Microdroplet Device
Biophysical Journal, 2012Co-Authors: Paul Abbyad, Remi Dangla, Pierre-louis Tharaux, Charles Baroud, Antigoni AlexandrouAbstract:We have developed a novel microfluidic device to study repetitive sickling on individual red blood cells by replicating the physiological oxygen cycling of the vascular circulatory system (Abbyad et al., Lab Chip, 2011, 11, 813). A small number of red blood cells from sickle cell patients are encapsulated in an array of aqueous microdroplets. These microdroplets are anchored and arranged in a 2-dimensional array against the flow of the Carrier Oil. Precise spatial and temporal changes in oxygen concentration are obtained through gas exchange with the inert Oil flowing outside the droplets.
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Sickling of red blood cells in microfluidic droplets
2010Co-Authors: Paul Abbyad, Pierre-louis Tharaux, Charles Baroud, Jean-louis Martin, Antigoni AlexandrouAbstract:Red blood cell sickling associated with sickle cell disease is affected by a complex interplay of vascular components and conditions which are not yet fully understood. A primary trigger of sickling is low oxygen partial pressure. Therefore, we have developed a microfluidic device to rapidly vary the oxygen partial pressure within flowing microdroplets. By using a Carrier Oil at a known oxygen partial pressure, a microdroplet was subjected to a deoxygenation at a rate that depends on both flow conditions and droplet size. The oxygen concentration in a single droplet was characterized with a ruthenium compound whose fluorescence lifetime is proportional to the oxygen concentration. The device was shown to provoke sickling of individual red blood cells which was readily detected by birefringence. The versatility of the same device was also demonstrated by initiating a chemical reaction in a microdroplet using a gaseous reactant.